• The Korean Journal of Physiology
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• v.30 no.2
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• pp.219-229
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• 1996

In order to investigate intra-pancreatic cholinergic roles on insulin action in exocrine secretion, the pancreas was isolated from rats and continuously perfused with modified Krebs-Henseleit solution. Intra-arterial infusion of insulin (100 nM) or cholecystokinin (CCK, 14 pM) alone resulted in stimulation of the volume flow and amylase output. Also insulin potentiated the action of CCK in the exocrine secretion. Tetrodotoxin and atropine completely abolished the potentiating action of insulin and CCK as well as the action of insulin alone, but did not change the action of CCK alone. In order to see an effect of intra-pancreatic neural activation on the insulin action, electrical field stimulation (EFS) with parameters of 20 V, 2 msec and 8 Hz was applied to the isolated pancreas for 10 min under 2.5 or 18 mM glucose background. The EFS voltage-dependently elevated the flow rate and amylase output, and potentiated exocrine secretion in 18 mM glucose infusion compared with 2.5 mM glucose. The potentiating effects of EFS and 18 mM glucose were not observed in the streptozotocin-treated pancreas although it was perfused with 18 mM glucose. However, it was restored when the diabetic pancreas was perfused with porcine insulin(100 nM). Tetrodotoxin and atropine inhibited the pancreatic secretion induced by EFS with the background of 18 mM glucose. The results of present investigation indicate that the intra-pancreatic cholinergic tone exerts a stimulatory influence on the action of insulin in pancreatic exocrine secretion of rats.

• Korean Journal of Childcare and Education
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• v.20 no.2
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• pp.59-81
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• 2024

Objective: This study aims to explore the intra-action between infants and picture book reading in a daycare setting, aiming to gain new insight into infants' reading experiences. Methods: The participants in the study were 12 infants from the Bluebird Class (1-year-old) at A Daycare Center. To comprehensively examine the context and flow of the infants' experiences, participant observation was conducted during free play sessions, held three to five times a week, in the morning, from December 19, 2022, to February 17, 2023. Results: Firstly, infants engaged in the intra-action with symbols such as text, images, lines, colors, and latent narratives in picture books, spontaneously encountering meaning-making. Secondly, they explored the potential of materials such as their own bodies, the dacare classroom environment, and blocks, creating narratives through the process of 'becoming'. Thirdly, infants generated shared experiences by creating interactions within their relationships with others in the daycare class. Conclusion/Implications: This study highlights a shift in perspective, recognizing infants as active readers who construct their own understanding. Additionally, it underscores the significance of cultivating an infant-centered environment and the meaningful role of teachers in supporting and facilitating such an environment.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.83-90
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• 1997

Aim of this study was to investigate if pancreatic polypeptide (PP) reduced the insulin action via the intra-pancreatic cholinergic nerves in the isolated rat pancreas. The pancreas was isolated from rats and perfused with intra-arterial infusion of modified Krebs-Henseleit solution containing 2.5 mM glucose at a flow rate of 1.2 ml/min. Simultaneous intra-arterial infusion of insulin (100 nM) resulted inpotentiation of the pancreatic flow rate and amylase output which were stimulated by cholecystokinin (CCK, 14 pM). These potentiating actions of insulin on the CCK -stimulated pancreatic exocrine secretion were completely abolished by administration of rat PP. Vesamicol, a potent inhibitor of vesicular acetylcholine storage, and tetrodotoxin (TTX) also significantly reduced the combined actions of insulin and CCK. Administration of carbamylcholine, an acetylcholine agonist, completely restored the vesamicol- or TTX-induced inhibition of the potentiation between insulin and CCK. Also rat PP failed to attenuate the restoring effect of carbamylcholine. Electrical field stimulation (15-30 V, 2 msec and 8 Hz) resulted in a significant increase in the pancreatic flow rate and amylase output in voltage-dependent manner. Effects of electrical field stimulation were augmented by endogenous insulin. Rat PP also suppressed the pancreatic exocrine secretion stimulated by electrical field stimulation. These observations strongly suggest that PP inhibits the potentiating actions of insulin on CCK -stimulated pancreatic exocrine secretion by suppression of the intra-pancreatic cholinergic activity in the isolated rat pancreas.

• The Korean Journal of Pharmacology
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• v.5 no.2
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• pp.141-148
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• 1969

The direct effect of isoproterenol on renal function, when given intravenously, is usually obscured by its potent hypotensive action. To obviate the latter action, isoproterenol was infused directly into one renal artery of the dog, the other kidney serving as a control for the general action. And following results were obtained. In the first series of experiments, the directic action of isoproterenol was ascertained. $1.0\;{\mu}g/kg/min$. reduced on both kidneys the urine flow, clearances of PAH and creatinine, as well as the amount of sodium excreted, but the effect was weaker on the experimental side than on contralateral side. With $0.1\;{\mu}g/kg/min$., two cases among 6 experiments showed marked diuresis, two cases no apparent effect, and another two marked antidiuresis on the experimental kidney, whereas the contralateral kidney exhibited antidiuresis in all cases. Further reducing the dose unmasked the diuretic action on the ,experimental kidney. In another series, the effects of isoproterenol on the blood flow distribution within the kidney and on sodium concentration gradient within the kidney tissue were observed. $0.05\;{\mu}g/kg/min$ isoproterenol markedly increased the medullary plasma flow and slightly increased total renal plasma flow and glomerular filtration rate, along with concomitant increase in the amount of sodium excreted and osmolar clearance, and decrease in reabsorption of free water. Sodium concentration gradient markedly decreased in the experimental kidney, reaching 2/3 of the value observed in the contralateral kidney at the papilla. It is thus concluded that isoproterenol exerts a diuretic action, when infused directly into a renal artery, and the mechanism of the action rests on its hemodynamic action, substantiated as the increase in glomerular filtration and in the medullary blood flow, resulting in washout of hyperosmolality produced by the coutercurrent multiplier system.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.137-143
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• 2022

Purpose : The purpose of this study was to evaluate the reliability analysis of the deep tendon reflex by using electromyography (EMG). Methods : The study was tested on 30 volunteers who are women in their 20s. Using an electronic reflective hammer of EMG, deep tendon reflex was measured on all subjects with the participation of three trained physical therapists as raters. First, the subjects were comfortably seated on a table with their knees bent at 90 °. The three raters tapped the electric hammer at intervals of 10 seconds to avoid habituation until a total of 10 compound muscle action potential records were collected. Intraclass correlation coefficients (ICCs) were calculated to assess the inter-rater reliability of the deep tendon reflex with the use of EMG. The items of analysis included amplitude (mV), latency (ms), duration (ms), and area (mV × ms) of the compound evoked potentials. Results : Based on the average records of 10 compound muscle action potential, excellent reliability (ICC: .912) was achieved in terms of area, and there was good reliability in terms of latency (ICC: .795) and duration (ICC: .800). In the shortest latency of the compound muscle action potential, good reliability was achieved in terms of amplitude (ICC: .865), duration (ICC: .781), and area (ICC: .832). In the amplitude of peak-to-peak of compound muscle action potential, excellent reliability was recorded in terms of amplitude (ICC: .924), and good reliability was recorded in terms of duration (ICC: .801) and area (ICC: .874). Conclusion : The findings in this study indicate that electromyography via an electric hammer is a reliable method of assessing and measuring deep tendon reflexes. Especially, it may be an excellent gauge in the area of average values of the compound muscle action potentials and the amplitude of peak-to-peak of compound muscle action potentials.

• The Journal of Korean Physical Therapy
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• v.29 no.5
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• pp.246-254
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• 2017

Purpose: Previous studies have reported that action observation training has beneficial effects on enhancing the motor task, such as balance and gait functions. On the other hand, there have been few studies combined with action observation training and auditory feedback. The purpose of this study was to determine the effects of action observation training with auditory feedback on the gait function in stroke patients with hemiparesis Methods: A total of 24 inpatients with post-stroke hemiparesis were assigned randomly to either an experimental group 1 (EG 1, n=8), experiment group 2 (EG 2, n=8), control group (CG, n=8, EG 1). The EG 2 and CG watched video clip demonstrating three functional walking tasks with auditory feedback, without auditory feedback, and showing a landscape image, respectively. The exercise program consisted of 30 minutes, five times a week, for four weeks. The participants were measured to 10MWT (10 m walk test), 6MWT (6 minutes walking distance test), TUG (timed up and go test), DGI (dynamic gait index), time and steps of F8WT (figure-of-8 walk test). Results: In the intra-group comparison after the intervention, EG 1 and EG 2 showed a significantly different gait function (10MWT, 6MWT, DGI, TUG, F8WT) (p<0.05). In the inter-group comparison after intervention, EG 1 showed significant improvements in the entire gait parameters and EG 2 only showed significant improvement in DGI and TUG compared to CG (p<0.05). Conclusion: These findings show that action observation training with auditory feedback may be used beneficially for improving the gait function of stroke patients with hemiparesis.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.4
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• pp.217-221
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• 2003

To clarify the roles of gonadal steroids on pancreatic exocrine secretion, effects of progesterone and estradiol-$17{\beta}$ on spontaneous and secretagogue-induced exocrine response of isolated perfused rat pancreas were investigated. Intra-arterial infusion of progesterone resulted in significant increase of the spontaneous pancreatic fluid and amylase secretion dose-dependently. However, estradiol-$17{\beta}$ did not exert any influence on spontaneous pancreatic exocrine secretion. Exogenous secretin, cholecystokinin (CCK), and acetylcholine markedly stimulated pancreatic fluid and amylase secretion. Progesterone initially enhanced secretin-induced amylase secretion, but this stimulatory response declined thereafter to basal value. Moreover, secretin-induced fluid secretion was not affected by infusion of progesterone. Therefore, initial increase of secretion-induced amylase secretion by progesterone seems to be a non-specific action by washout effect of secretin. Estradiol-$17{\beta}$ failed to change the secretin-induced fluid and amylase secretion. Both progesterone and estradiol-$17{\beta}$ did not exert any influence on CCK-induced fluid and amylase secretion. Acetylcholine-induced exocrine secretion of isolated perfused pancreas also was not affected by intra-arterial infusion of progesterone or estradiol-$17{\beta}$. It is concluded from the above results that progesterone could enhance the spontaneous pancreatic fluid and amylase secretion of isolated perfused rat pancreas through non-genomic shortterm action, and that these effects could be masked by more potent stimulants such as secretin, CCK, and acetylcholine.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.245-257
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• 1988

The present study was undertaken to investigate the effect of clonidine on the response of the dorsal horn cells to intra-arterially administered bradykinin $(BK:40{\mu}g)$ and $K^+(4mg)$ in spinal cats and cats with intact spinal cord. The change in the activities of low threshold (LT), high threshold (HT) and wide dynamic range (WDR) cells induced by BK and $K^+$ were determined before and after treatment of animals with clonidine. Also studied was mechanism of inhibitory action of clonidine on the responses of dorsal horn cells to the chemical algogenics. Number of WDR cell responded to intra-arterially administered BK and $K^+$ was greater in spinal animals than in cats with intact spinal cord. Following administration of BK or $K^+$ no change was observed in the activity of LT cell whereas activity of HT cell increased invariably. The increased response of HT cell to BK and $K^+$ was markedly suppressed by clonidine. On the other hand, such inhibitory actions of clonidine were almost completely blocked by yohimbine. The majority of WDR cells were activated by $K^+$ while response of WDR cells to BK was diverse (excitatory, inhibitory or mixed). These results indicate that clonidine inhibits responses of the dorsal horn cells not only to thermal or mechanical stimulations but also to chemical algogenics, and that the inhibitory action of clonidine is generally mediated through excitation of ${\alpha}_2-adrenoreceptors$.

• The korean journal of orthodontics
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• v.54 no.5
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• pp.316-324
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• 2024

Objective: To evaluate tooth displacement and periodontal stress generated by the dual action vertical intra-arch technique (DAVIT) for open-bite correction using three-dimensional finite element analysis. Methods: A three-dimensional model of the maxilla was created by modeling the cortical bone, cancellous bone, periodontal ligament, and teeth from the second molar to the central incisor of a hemiarch. All orthodontic devices were designed using specific software to reproduce their morpho-dimensional characteristics, and their physical properties were determined using Young's modulus and Poisson's coefficient of each material. A linear static simulation was performed to analyze the tooth displacements (mm) and maximum stresses (Mpa) induced in the periodontal ligament by the posterior intrusion and anterior extrusion forces generated by the DAVIT. Results: The first and second molars showed the greatest intrusion, whereas the canines and lateral incisors showed the greatest extrusion displacement. A neutral zone of displacement corresponding to the fulcrum of occlusal plane rotation was observed in the premolar region. Buccal tipping of the molars and lingual tipping of the anterior teeth occurred with intrusion and extrusion, respectively. Posterior intrusion generated compressive stress at the apex of the buccal roots and furcation of the molars, while anterior extrusion generated tensile stress at the apex and apical third of the palatal root surface of the incisors and canines. Conclusions: DAVIT mechanics produced a set of beneficial effects for open-bite correction, including molar intrusion, extrusion and palatal tipping of the anterior teeth, and occlusal plane rotation with posterior teeth uprighting.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.11
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• pp.127-136
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• 2007

An abrupt scene-change frame is one that is hardly correlated with the previous frames. In that case, because an intra-coded frame has less distortion than an inter-coded one, almost all macroblocks are encoded in intra mode. This breaks up the rate control flow and increases the number of bits used. Since the reference software for H.264 takes no special action for a scene-change frame, several studies have been conducted to solve the problem using the quadratic R-D model. However, since this model is more suitable for inter frames, the existing schemes are unsuitable for computing the QP of the scene-change intra frame. In this paper, an improved rate control scheme accounting for the characteristics of intra coding is proposed for scene-change frames. The proposed scheme was validated using 16 test sequences. The results showed that the proposed scheme performed better than the existing H.264 rate control schemes. The PSNR was improved by an average of 0.4-0.6 dB and a maximum of 1.1-1.6 dB. The PSNR fluctuation was also in proved by an average of 18.6 %.